Migrate WTF::Vector::append() to ::push_back() [part 2 of N]

third_party/WebKit/Source/core/animation/css/CSSAnimationData.cpp

Index: third_party/WebKit/Source/core/animation/css/CSSAnimationData.cpp
diff --git a/third_party/WebKit/Source/core/animation/css/CSSAnimationData.cpp b/third_party/WebKit/Source/core/animation/css/CSSAnimationData.cpp
index 652abcfd928333b72ff82203f75d5f10385c169b..2c4a739930479f63f291d4709962870b1577f8f7 100644
--- a/third_party/WebKit/Source/core/animation/css/CSSAnimationData.cpp
+++ b/third_party/WebKit/Source/core/animation/css/CSSAnimationData.cpp
@@ -9,11 +9,11 @@
 namespace blink {
 
 CSSAnimationData::CSSAnimationData() {
-  m_nameList.append(initialName());
-  m_iterationCountList.append(initialIterationCount());
-  m_directionList.append(initialDirection());
-  m_fillModeList.append(initialFillMode());
-  m_playStateList.append(initialPlayState());
+  m_nameList.push_back(initialName());
+  m_iterationCountList.push_back(initialIterationCount());
+  m_directionList.push_back(initialDirection());
+  m_fillModeList.push_back(initialFillMode());
+  m_playStateList.push_back(initialPlayState());
 }
 
 CSSAnimationData::CSSAnimationData(const CSSAnimationData& other)